RF sealing is employed in test and production environments where the amount of radiation emitted or absorbed by an electronic device must be closely controlled. Excess RF exposure can lead to erroneous test results, or in production and operational environments, degrade the performance of equipment sensitive to the emitted radiation. RF sealing is also important when an electronic component emits sufficient radiation to impact the performance of other proximate electronic components. In this second case, RF sealing isolates the source of radiation, while the first case may be used to isolate sensitive RF components.
RF enclosures may be used in a variety of test and measurement applications when the amount of RF radiation that impacts a device under test (DUT) must be carefully controlled. Specific examples include prototype testing and production testing of cellular telephones, portable computers, pagers, and other small electronic devices. Often RF enclosures are used in automated or semi-automated environments in which machines are used to place the DUT inside the RF enclosure. In these types of test environments, it is desirable to be able to evaluate the functionality and correct operation of the DUT while the DUT is within the RF enclosure. The use of electronics circuitry and software may be used to apply specific test resources to the DUT and measure the responses. In most applications, the electronics circuitry and software are located both internal and external to the RF enclosure. Some of the electronics circuitry located internal to the RF enclosure, as well as the test functionality being controlled by the electronics, are specific to a particular type of DUT. An example of this is isolation testing of cellular phones from different manufacturers. Each phone has particular testing requirements that necessitate the use of specialized test functionality. An important issue that arises in the design of an RF fixturing device is the speed and facility with which device specific resources, also called customizations, can be replaced. This need to replace customizations can occur in a production test environment in which the DUT is changed and the RF test fixture needs to be quickly modified to match the testing requirements of the new DUT. The need for a quick replacement of device specific resources could also occur in a production environment when the device specific resources of the RF test fixture reach the end of their life cycle and fail.
The electronics and device specific resources, or customization, are located on a mechanical support and interface structure. This mechanical interface structure serves as the primary point of contact between a customization and the remainder of the RF test fixture. Thus, the need to replace device specific resources is often translated into the need for a mechanical interface and the associated interface that is easily replaced.
Many solutions exist which allow the replacement of the customization in an RF test fixture. Typically, these solutions use numerous pneumatic fittings and expensive custom designed electrical connections to accomplish this. Many require the user to disconnect pneumatic hoses and/or electrical connections individually, which adds complexity to the replacement of the customization. This adds to the time required to replace the customization and also opens the possibility of making errors in reconnecting the hoses and electrical connections causing damage to the fixture or customization. Since the interface is complex, time to develop additional customizations can be excessive. An additional issue with replacing the customization is creating a strong seal between the customization and the RF fixture. Prior solutions for making a pneumatic seal in a removable customization in an RF enclosure have been to use coupling connectors. These fittings are expensive, require additional parts and machining, require force to engage, and take up space in the customization.
Thus, there is an unmet need in the art for a RF fixturing system that contains customizations that may be quickly and easily removed, without disconnecting multiple pneumatic hoses and electrical connections individually. There is a further need in the art for a mechanical seal interface supporting a customization that does not require force to engage the seal, and requires very little space in the customization